Quick question on 3 phase before my final

[tanky322]

Quick question on 3 phase before my final!

Homework Statement

In equations for 3 phase power there is an angle that is mentioned, but I don't know if this is the angle of the impedance or another angle. I am a little confused. The equations are below.

Homework Equations

P=(VrmsIrms)cos($$\theta$$)
Q=(VrmsIrms)sin($$\theta$$)


Any help?

 

[PhanthomJay]

Homework Statement

In equations for 3 phase power there is an angle that is mentioned, but I don't know if this is the angle of the impedance or another angle. I am a little confused. The equations are below.

Homework Equations

P=(VrmsIrms)cos($$\theta$$)
Q=(VrmsIrms)sin($$\theta$$)


Any help?

I'm certainly not an electrical expert, but the angle you are referring to is the phase angle betwen the voltage and the current, where $$cos\theta = power factor$$. For purely resistive loads, theta is 0, hence the power factor is unity, and there is no reactive power Q. However, I don't quite understand your equation, since typically ,for power transmsission, $$P= \sqrt3(V)(I)cos\theta$$. That's about it for my electrical knowledge.

 

[piercas]

I can understand your confusion about the angle mentioned in 3 phase power equations. This angle is known as the power factor angle and it represents the phase difference between the voltage and current in a three-phase system. It is not the angle of the impedance, which is represented by the symbol 'Z'. The power factor angle is important because it affects the efficiency and power consumption of a three-phase system. A higher power factor angle means a lower power factor, which results in more energy being wasted. Therefore, it is important to calculate and consider the power factor when working with three-phase power equations. I hope this helps clarify your question. Good luck on your final!